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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Sun & climate: moving in opposite directions

What the science says...

The sun's energy has decreased since the 1980s but the Earth keeps warming faster than before.

Climate Myth...

It's the sun
"Over the past few hundred years, there has been a steady increase in the numbers of sunspots, at the time when the Earth has been getting warmer. The data suggests solar activity is influencing the global climate causing the world to get warmer." (BBC)

Over the last 35 years the sun has shown a cooling trend. However global temperatures continue to increase. If the sun's energy is decreasing while the Earth is warming, then the sun can't be the main control of the temperature.

Figure 1 shows the trend in global temperature compared to changes in the amount of solar energy that hits the Earth. The sun's energy fluctuates on a cycle that's about 11 years long. The energy changes by about 0.1% on each cycle. If the Earth's temperature was controlled mainly by the sun, then it should have cooled between 2000 and 2008.

The solar fluctuations since 1870 have contributed a maximum of 0.1 °C to temperature changes. In recent times the biggest solar fluctuation happened around 1960. But the fastest global warming started in 1980.

Figure 2 shows how much different factors have contributed the warming. It compares the contributions from the sun, volcanoes, El Niño and greenhouse gases. The sun adds 0.02 to 0.1 °C; volcanoes cool the Earth by 0.1-0.2 °C; natural variability (like El Niño) heats or cools by about 0.1-0.2 °C; and greenhouse gases have heated the climate by about 0.8 °C.

Some people try to blame the sun for the current rise in temperatures by cherry picking the data. They only show data from periods when sun and climate data track together. They draw a false conclusion by ignoring the last few decades when the data shows the opposite result.

Further viewing

Comments

Re Quietman -
"Chapter 6 is essentially written for the layman, not much actual information, just speculation:"

... sounds like the summary. It goes further and discusses evidence and theory.

"Overall the statements made in the entire PDF are based on the GHG hypothesis being factual as presented by Hansen. IF you accept his hypothesis"...

I don't remember offhand if it mentions continental drift and geologic outgassing changes, but ... it might; there is mention of the PETM. Anyway, most climatologists are well aware that there are other factors that work alongside CO2 and also work through and from CO2, and the IPCC is not trying to state otherwise. There is certainly discussion of Milankovitch cycles and - I don't remember for sure if it appears in chapter 6, but internal variability is definitely discussed within the IPCC AR4 WGI.

Furthermore, remember that climate theory holds that CO2 and other greenhouse gases affect climate via LW radiative forcing. Climate theory is not that CO2 is the only important factor in all climate changes for all time. Application to the present situation strongly suggests that we should expect that anthropogenically-forced changes in atmospheric CO2,CH4,etc. levels will have a significant warming effect, and the natural forcing changes that have occured in the comparable time periods have been small by comparison; what has yet to be demonstrated or shown as a strong contender is that the climate is much much more sensitive to solar TSI, solar UV, or much much much more sensitive to solar wind and geomagnetic effects or tidal forcings, then it is to other forcings in general, and in the absence of robust evidence and/or theoretical foundations, it is hard to give much credence to the ideat that more than a relatively small bit of recent changes are due to such forcings. In contrast, theory and evidence together and each in isolation make a case for the sensitivity of climate to Milankovitch cycles when near or within some threshold range, as well as for the more general 3 +/- 1 deg C per 4 W/m2 tropopause level radiative forcing sensitivity for many other forcings such as from CO2.

"What it actually indicates is that CO2 follows temperature and is powerless to stop natural cooliing."

The robust correlation of CO2 to temperature merely shows that there is a relation; the actual causal links must be elicidated by combining paleoclimatic data with laboratory data (radiative properties, ideal gas laws, momentum conservation, dishpan experiments of general circulation, isotopic studies) and computer models based on physics and data.

"By not looking at WHY CO2 follows temperature they make a grave error and that makes the recommendations misleading. Temperature increases allow increased biomass, both flora and fauna. In warmer climate the increased biomass creates the increased CO2 by simply breathing."

They actually do look at why CO2 follows temperature but there are significant uncertainties remaining. What has been established is that it is very likely that in the ice ages, relative to interglacials, C is removed from the atmosphere, biomass, also maybe soils, and the upper mixed layer of the ocean (lower temperature increases the equilibrium CO2 concentration in water for a given concentration in air, but not enough to have CO2 concentration in the surface water stay the same or increase when the atmospheric decrease was so large), and given the slowness of the geological branches of the C cycle, the deep ocean is the best candidate for where the C went.

Your proposed mechanism doesn't seem likely. The amount of biomass today is comparable to the amount in the atmosphere and is less than in the soil. A decrease in biomass means that there is C that is not in biomass - where did it go? The soil, the atmosphere, the upper ocean, and/or the deep ocean? Simply having more biomass does not increase the atmospheric CO2 by breathing; biologically-driven changes in C levels are determined by imbalances between photosynthesis and respiration/oxydation and by where these things occur.

"Are you starting to see my issue with chris here? This is exactly what I tried to point out earlier. Those of us in non-theoretical sciences and professions follow the laws of thermodynamics to practical ends and know that they can not be violated. They simply can not be applied to open systems, ie. living things and the earth itself precisely because they are open systems. It's the reason that climate models do not work."

No. I may have made some terminological slip ups (enthalpy vs internal energy vs thermal energy vs heat), but by and large, on the points where disagreement occurs, I AM right, Gord IS wrong - and just try to find a physics or engineering department that disagrees.

Yes both the summary and the details only concern the relationship of CO2 to Temperature under all the known variables so much information isn't there. I say it's for the layman as none of the infoermation was anything that I was not already aware of and commonly available for anyone interested. I just happen to be interested. Some of the facts covered have been known since the late 1800s, some are as recent as about 20 years.

"Your proposed mechanism doesn't seem likely. The amount of biomass today is comparable to the amount in the atmosphere and is less than in the soil. A decrease in biomass means that there is C that is not in biomass - where did it go? The soil, the atmosphere, the upper ocean, and/or the deep ocean? Simply having more biomass does not increase the atmospheric CO2 by breathing; biologically-driven changes in C levels are determined by imbalances between photosynthesis and respiration/oxydation and by where these things occur."

Obviously I disagree. The KT extinction killed off ALL large fauna and destroyed a good portion of the flora as well. So we had a situation where O2 and CO2 were high and the new species developed in an O2 rich atmosphere whereas the dinosaurs had been born into an O2 poor atmosphere and plants that did not get the full benefit of CO2. ie. new types of plants took over and with them new types of fauna (not that the genera were new but now they increased in diversity and population).

Mammals use much more O2 and consequently produce more CO2 as byproduct. The warmer it gets the wider the range and the larger the populations. Grass was relativly new and naturally followed by grass eaters which causes more methane as that is the nature of grazing animals.

And of course their is the constantly evolving bacteria. The largest part of the biomass by far in the air, on the surface and below it, in the water and in the muck below it, all do well in warm conditions.

Then of course there is plate tectonics and the consequences thereof on ocean currents and climate.

In short, there are multiple causes for CO2 following temperature and they all point to life itself.

Nothing to do with CO2 or temperatures. The PETM was roughly 55 million years ago, we evolved from primitive primates to prosimians in Asia, this was a benefit to our own ancestors.

The PT extinction was an ocean impactor near Antarctica destroying nearly 90% of marine species. Like the KT impact we had the creation of traps on the opposite of the impact (Deccan Traps), in this case the Siberian Traps. The subsequent terrestrial extinction was not quite as bad at roughly 70% of species. There is good reason to suspect the Bedout crater but this is as large an argument as the KT extinction.

I could go on but this is not the right thread for it, I think "Climate Changed Before" would be more appropriate.

But don't let me interfere with your discussion with Gord. In the mean time I'll go through my notes and find some references for you (to post in the other thread as mentioned).

Elaborating on what I was explaining, the second law of thermodynamics is a description of what may and may not be reversable. A necessary condition for reversability is that entropy is conserved - thus, a reversable process is an isentropic process, - examples include adiabatic processes (sound familiar? isentropes, potential temperature, etc.), wherein there are no heat flows across system boundaries...

An increase in entropy cannot be reversed.

Notice how different this is from some more fundamental physics. Consider the conservation of momentum and energy, reaction and reation: if a billiard ball hits another billiard ball in an elastic collision (so that none of the macroscopic energy is transferred to random molecular motions, etc.), however they bounce, one can take positions at time t after the collisions, and from that point, if the spins and velocities are precisely reversed, the collision runs in reverse, producing the exact reverses of spins and velocities, backwards along the same trajectories, as had initially occured before the collision. This is part of a general pattern in physics - in gravity (an orbit works backwards and forwards), electromagnetism, etc.

Irreversability occurs because the chances of producing the precise setup for reversal as in the above example can be quite small, and for a system with many components, an arrangement of components that is identifiable as special (lower entropy) from the macroscopic scale is less likely to occur if the arrangement is chosen at random. Higher entropy states are states wherein a larger subset of possible arrangements (states differentiable on the microscopic scale - precise positions of each individual component) will produce the same macroscopic state, so that there is a greater chance of achieving such a macroscopic state. Hence, random processes on the microscopic level tend to increase entropy, and this is irreversable because of the low probability of the system finding a 1 in a million arrangement that is noticeability 'special' (low entropy) on the macroscopic scale.

Well, I can't really argue with you so much about the PT extinction except to say that the role of the Siberian traps' CO2 emissions over a million(s?) years(even if caused by an impact) might be expected to be significant.

"Nothing to do with CO2 or temperatures. The PETM was roughly 55 million years ago, we evolved from primitive primates to prosimians in Asia, this was a benefit to our own ancestors."

PETM seems to have been caused either by a large CO2 release, a large CH4 release (that would eventually oxidize to CO2), or maybe both. It might have been triggered by volcanism but may have involved destabilization of CH4 hydrates, rather than being direct geological emissions of CO2. There was a temperature increase. It was not a mass extinction on the scale of KT or PT, but there was at least some ecological disruption (I just don't know the magnitude offhand as suggested by the evidence). Sure, we may owe our existence to it. We also owe our existence to KT and PT mass extinctions. We don't need to replicate those things to continue our existence.

"And of course their is the constantly evolving bacteria. The largest part of the biomass by far in the air, on the surface and below it, in the water and in the muck below it, all do well in warm conditions."

In terms of biomass, they might have some competition from krill (?). They certainly do evolve, but the plethora of metabolic pathways (photosynthesis types..., fermentation, respiration, methanogens and methanotrophs, sulfate reduction...) has not changed much for a long time.

Your timings and causes are incorrect Quietman. The collision of the African and Eurasian plates that "squeezed out" the Tethys Ocean and drove the crumpling and nappe formation that raised the Alps occurred 20-ish million years ago. It had nothing to do with the PETM.

The PETM was an event of widespread gobal warming and considerable extinctions associated with the massive release of greenhouse gases. It coincides temporally (as Patrick has indicated) with the opening up of the North Atlantic as the plates seperated centered around what is now Iceland, and dated around 55-56 million years ago. Whatever the ultimate cause of the release of the greenhouse gases (both CO2 and methane are implicated) the evidence indicates a very massive (several thousand gigatonnes) release of isotopically-light carbon (i.e. tectonically-derived, or methane hydrates...) into the atmosphere.

abstract: “The Paleocene-Eocene thermal maximum (PETM) has been attributed to a sudden release of carbon dioxide and/or methane. 40Ar/39Ar age determinations show that the Danish Ash-17 deposit, which overlies the PETM by about 450,000 years in the Atlantic, and the Skraenterne Formation Tuff, representing the end of 1 ± 0.5 million years of massive volcanism in East Greenland, are coeval. The relative age of Danish Ash-17 thus places the PETM onset after the beginning of massive flood basalt volcanism at 56.1 ± 0.4 million years ago but within error of the estimated continental breakup time of 55.5 ± 0.3 million years ago, marked by the eruption of mid-ocean ridge basalt–like flows. These correlations support the view that the PETM was triggered by greenhouse gas release during magma interaction with basin-filling carbon-rich sedimentary rocks proximal to the embryonic plate boundary between Greenland and Europe.”

The inability (within bounds of random 'error' of microscopic events - being random, these 'errors' might just contribute to entropy anyway) for a system to spontaneously reduce entropy without increasing entropy elsewhere is a result of the statistics and probability of microscopic processes.

It is not a result of some 'physical force' that actually drives heat from a hot object to a cold object in the same way that gravity pulls matter together and electromagnetism describes the interaction of charged particles, etc.

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Regarding heat transfer by radiation:

Radiation is emitted when there are energy transitions between two states available of the kind that will emit radiation (of a particular energy, polarization, direction) and the system (or the relevant portion of it - an electron, a molecule, a crystal lattice) is in the more energetic state. This happens, as I understand it, with some rate of decay - except for stimulated emission (as in a laser), which is dependent on electromagnetic waves passing by, the energy transition between states happens randomly in time, with some probability over any interval of time, so that a population of such energized states will decay exponentially. When a system is in the lower energy state of such a pair of states, there is some probability that radiation of some energy, polarization, and direction, will be absorbed by the system.

Other energy transitions can occur without radiation, or with radiation at a different energy, etc, that will put energy into such states so that it can emit radiation, and energy transitions may remove a system from such states without emitting radiation, or emitting radiation at a different energy, etc.

The greater the occupancy of some set of states in a system, the greater the rate at which energy transitions will occur to reduce that occupancy.
However energy is distributed in a system, a tendency toward thermodynamic equilibrium results in a redistribution of energy until the distribution of energy is such that energy transitions occur at the same frequency as their reverse transitions. What determines blackbody radiation intensity is how much radiant energy there must be for a system at a given temperature to absorb radiant energy at the same rate that it emits radiant energy.

"Those of us in non-theoretical sciences and professions follow the laws of thermodynamics to practical ends and know that they can not be violated. They simply can not be applied to open systems, ie. living things and the earth itself precisely because they are open systems. It's the reason that climate models do not work."

1.
Did my textbooks and college and high school courses not benifit from actual experiments as well as mathematical derivations, etc?

Being in the field has value.

However, if we are not allowed to stand on the shoulders of giants, how would our science and technology (and philosophy, politics, etc.) ever progress?

Furthermore, Gord and some others with related arguments are arguing points that can easily be argued against based on rather simple observations from everyday life, basic logic, and just a general understanding of physics; it isn't really necessary to know all the ins and outs of QED to see that Gord's version of the 2nd law required some rather miraculous processes.

2.
To say that climate models do not work is innaccurate. They are not perfect but they are good enough for some purposes (probably better than you think). Often in science, technology, and life, there is an important role for useful approximations.

3.
It isn't actually necessary to use the second law to analyze the entire system as a whole. That would actually not be so helpful in producing a model.

Instead:

Use the ideal gas laws and thermodynamics on the small scale. When air changes pressure and then a diabatic heating or cooling occurs, the changes in temperature and density are quite predictable. Some microscopic and small scale processes (momentum, thermal, and mass diffusion and turbulent mixing) - though they can be modelled individually - cannot be modelled explicitly as part of a general circulation model because of limited computing power, but they are understood and can be parameterized.

In other words, the underlying physics are understood. The only real limitations are limited computing power, so that the model's grid scale cannot resolve all processes explicitly, so that some processes have to be parameterized, but those processes can be understood.

A human is not a closed system; mass goes in and out, energy goes in and out in various forms; yet, we understand fairly well the consequences of eating more or less of at least the macronutrients, excercising, and what happens if you jump in the air (aside from air drag, your center of mass will accelerate downward at approximately 9.8 m/s^2)...

You said...
"Furthermore, Gord and some others with related arguments are arguing points that can easily be argued against based on rather simple observations from everyday life, basic logic, and just a general understanding of physics; it isn't really necessary to know all the ins and outs of QED to see that Gord's version of the 2nd law required some rather miraculous processes."

I find this statement typical of your posts.
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First, there is no "Gord's version of the 2nd law".

"Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object."

http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw.html#c3

I did not write the above description of the 2nd Law nor have I attempted to CHANGE IT, as you have!

The 2nd Law of Thermodynamics is a FUNDAMENTAL LAW OF SCIENCE and there is absolutely nothing "miraculous" about it!

You have stated your "opinions" regarding the 2nd Law and actually pretend to have presented evidence that the 2nd Law is somehow lacking.

This is readily apparent in your statement that I quoted above.
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Your posts are a just a jumble of "opinions" with absolutely no supporting evidence at all.

What you call "simple observations", "basic logic" and "a general understanding of physics" is about as far away as you can get from a rational reading of the, extremely clear, 2nd Law of Thermodynamics.

In fact, your posts continually use "opinion examples" that not only violate the 2nd Law, they also clearly violate the Law of Conservation of Energy, Electromagnetic Field Physics, Radiative Heat transfer equations, Vector mathematics and actual measurements.

Sometimes your posts include rambling opinions and questions that are really "astounding" and demonstrates a total inability to understand even basic physics.

The sheer quantity of these opinions and questions (that are so easily answered by most high school science students) are just too tedious to respond to.
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Most "Scientific" debates start with the acceptance of basic Laws of Science as being valid and proceed from there.

Opinions and statements are backed up with supporting evidence and verified scientific measurements.

Gord, for the last time (PS thought you weren't going to respond to me anymore, but I guess we both can't resist the urge to respond):

Nothing I've argued goes against high school science or science at any level.

If most scientific debates start with acceptance of basic laws, why do you refuse to accept the laws of blackbody radiation (Planck's formula, etc.) - demonstrated by experiments, and clearly given in the same "hyperphysics" website that you quote for the second law.

You have turned that one part of a website into a religious scripture that can only be understood your way - while other parts of the SAME website require a different interpretation when it comes to radiative energy fluxes.

"The 2nd Law of Thermodynamics is a FUNDAMENTAL LAW OF SCIENCE and there is absolutely nothing "miraculous" about it!"

It is not as fundamental as gravity and electromagnetism, relativity and quantum mechanics, and the conservation laws, and the laws of motion, etc, in the sense that the second law describes behaviors of systems that are obeying these other laws and not doing anything highly improbable (like all the molecules in some macroscopic object suddenly moving in the same direction and speed as a result of random processes on a spatial scale smaller than the macroscopic object). On the other hand, one could consider it more fundamental because it could be expected to apply to a variety of other universes with other physical laws.

I agree that it is not miraculous. Your interpretation of it requires miraculous events - that an object emits or does not emit a photon depending on the temperature of another object at some distance and at a future time.

I suspect your work with electromagnetic waves was limited to the macroscopic level (and perhaps had nothing to do with thermal emissions, but rather with emission of waves due to some work input - organized electrical currents and magnetic fields, etc.). For shorter wavelengths, particularly those in which the bulk of radiant energy is emitted thermally at temperatures typical of the Earth and atmosphere, or at any higher temperatures, it is convienient to think of photons. Feel free to take a vector sum of energy fluxes from all linearly superimposed electromagnetic waves if you want to - there is nothing wrong with that, you will get the net energy flux, but this does not change the fact that photons often go by the same location in space in many directions, including opposite directions, and for radiation in thermodynamic equilibrium within some isothermal expanse of sufficient opacity, provided isotropic refraction properties of the medium, photons at each energy will be evenly distributed among all directions, all polarizations, all times within a given time interval, all locations within the region considered. For thermal emissions, net flux of photons and thus of their energy is caused by some temperature gradient that can be 'seen' at the wavelength considered - that is, the medium is not too opaque to hide temperature variations from view but not too transparent or reflective (some of the opacity has to be from emissivity) to let those temperature variations be invisible.

If you don't trust physicists, talk to other engineers. Ask them about the thermodynamics of blackbody radiation.

""Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object.""

The question of interpretation arises from this:

DEFINE HEAT.

Apparently hyperphysics defines heat as the net flow of energy when it comes to photons, and perhaps would not consider linearly superimposed fluxes that are components of the whole process to be heat fluxes individually. Is that correct or incorrect? It doesn't matter so much to me - it's just a matter of defining the word; I already understand the concept.

You said...
"Nothing I've argued goes against high school science or science at any level."

Yes you have!
I will show just a few of many, many examples.
----------------------------
"Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object."

http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw.html#c3

Here are some of your posts regarding the 2nd Law of Thermodynamics:
---
Your Post #253
"With regards to the second law of thermodynamics, what it says about spontaneous heat flow only being from warmer to cooler and not the other way around - it is important to remember that this is NET flow. The NET flow of heat can be and often is the difference between two larger values, the heat flow only in one direction and the heat flow in the opposite direction."
---
Your Post #259
With reference to my statement about the 2nd Law "I don't see any mention of "NET" heat flow."

You said...
"Okay, but that's what they mean. The world doesn't make sense if otherwise - why?"

"The atmsophere and surface both radiate in each other's directions and recieve some of each other's emissions. This happens because while one is colder than the other, niether is at absolutely zero, nor is either perfectly transparent at all relevant wavelengths. The atmosphere does thermally emit radiation, and some of it reaches the surface."
---
In both cases you have re-written the 2nd Law of Thermodynamics based entirely on your "Opinion"!

In fact, a "NET flow" contradicts "not possible", which is part of the 2nd Law description!

This is a rather hilarious modification of the 2nd Law that any high school science student would easily pick up.
----------------------------
With regard to the incoming Solar Flux of 342 w/m^2 (the ONLY energy source) and The Law of Conservation of Energy:

Your Post #281
"The conservation of energy implies that if an object absorbs more energy than it emits, it will have a net energy gain. If it absorbs less than it emits, it will have a net energy loss."

"Set aside the second law of thermodynamics for a moment; having radiant fluxes greater than 342 W/m2 does not violate the conservation of energy."

"Mutual exchange of radiant energy could not be used to drive a perpetual motion machine by breaking the conservation of energy because it does not break that law."
---
ANY flux that EXCEEDS the 342 w/m^2 of THE ONLY ENERGY SOURCE is an UNDISPUTABLE VIOLATION OF THE LAW OF CONSERVATION OF ENERGY!

Again, ANY high school science student would easily pick up the obvious errors you made in your post.
---------------------
I will re-post part of my post #243 that has the definition of a Perpetual Motion Machine:

Perpetual motion
"The term perpetual motion, taken literally, refers to movement that goes on forever. However, the term more generally refers to any closed system that produces more energy than it consumes. Such a device or system would be in violation of the law of conservation of energy, which states that energy can never be created or destroyed."

"Perpetual motion violates either the first law of thermodynamics, the second law of thermodynamics, or both"

"A perpetual motion machine of the first kind produces energy from nothing, giving the user unlimited 'free' energy. It thus violates the law of conservation of energy."

http://en.wikipedia.org/wiki/Perpetual_motion
---
Patrick, your Posts above have violated both the 2nd Law of Thermodynamics AND The Law of Conservation of Energy and in FACT, describes a perpetual motion machine.

You have done this numerous times in your other posts as well.

ANY, high school science student would easily see how you have created a perpetual motion machine.
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----------------------
Once again, I only managed to get past the second line of your post #334 before the tedium of response became too much to handle.

The rest of your post #334, posts #335, #336 and #337 are rife with errors and unsupported rambling opinions.

Far too many errors and to go into at this time, however, I will repeat what I have already posted:
---------------
Your posts are a just a jumble of "opinions" with absolutely no supporting evidence at all.

What you call "simple observations", "basic logic" and "a general understanding of physics" is about as far away as you can get from a rational reading of the, extremely clear, 2nd Law of Thermodynamics.

In fact, your posts continually use "opinion examples" that not only violate the 2nd Law, they also clearly violate the Law of Conservation of Energy, Electromagnetic Field Physics, Radiative Heat transfer equations, Vector mathematics and actual measurements.

Sometimes your posts include rambling opinions and questions that are really "astounding" and demonstrates a total inability to understand even basic physics.

The sheer quantity of these opinions and questions (that are so easily answered by most high school science students) are just too tedious to respond to.
----------------------
Most "Scientific" debates start with the acceptance of basic Laws of Science as being valid and proceed from there.

Opinions and statements are backed up with supporting evidence and verified scientific measurements.

OMG, how could you not be getting this!!!??? (Do you not want to get this? Has this whole exchange been a joke to you?)

"Once again, I only managed to get past the second line of your post #334 before the tedium of response became too much to handle."

THEN CONSIDER THIS THIRD LINE:

"If most scientific debates start with acceptance of basic laws, why do you refuse to accept the laws of blackbody radiation (Planck's formula, etc.) - demonstrated by experiments, and clearly given in the same "hyperphysics" website that you quote for the second law."

----------

"In both cases you have re-written the 2nd Law of Thermodynamics based entirely on your "Opinion"!"
...
"The rest of your post #334, posts #335, #336 and #337 are rife with errors and unsupported rambling opinions."

Are high school and college level physics/science textbooks based entirely on someone's opinion? Are they just someone's unsurported ramblings? (You find a typo here and there, of course, but there's a bigger picture here.)

"Yes you have!"[contradicted laws of physics]

That's only your opinion, Gord, and not once have you backed it up; it's sad if you think you have.

----------

""The NET flow of heat can be and often is the difference between two larger values, the heat flow only in one direction and the heat flow in the opposite direction.""

IF there is a problem with that statement, it is simply incorrect terminology. YOU had identified each individual flux of energy in Kiehl and Trenberth's diagram as a flow of heat, and I also tend to think of it the same way, but the "hyperphysics" website seems to imply otherwise, implicitly defining THE flow of heat as the NET of non-work energy flows. The strict definition of heat given by "hyperphysics" includes the flow of heat that most of us would call a flow of heat, but it excludes other things most of us casually refer to as heat: internal energy, thermal energy, enthalpy (which can be confusing because 'heat capacity' sounds like it means the amount of heat an object can hold for each unit of temperature increase, whereas, as is implied by "hyperphysics", technically it only means the amount of heat an object gains/loses for each unit temperature change) - and furthermore, a distinction is made between internal energy and thermal energy, the later apparently excluding potential energy involved in molecular motions, etc., which is not how I am used to thinking of it.

"In fact, a "NET flow" contradicts "not possible", which is part of the 2nd Law description!"

No, it is not possible for the NET flow to spontaneously be from cooler to warmer...

What is impossible is for a spontaneous decrease in entropy in a closed system - it is impossible for THE flow of heat to be from cooler to warmer spontaneously - but that can be the net flow of internal energy, thermally-emitted photons, etc. AND I EXPLAINED WHY.

-------------------

"The term perpetual motion, taken literally, refers to movement that goes on forever. "

Are you now going to say that in a closed system, an electron in an atom must eventually stop moving (and not just pause, but completely stop)?

Are you saying that within an object at room temperature, all molecular-scale motions must eventually cease, even if the object remains at room temperature?

And so on with chemical equilibrium (that the forward and reverse reactions must both eventually cease?), and radiative equilibrium (that the energy density of photons within a chamber must go to zero?), even if those chemicals, and that chamber, remain at some nonzero temperature?

THESE phenomena are not what is meant when one speaks of a perpetual motion machine. The continual molecular motion, the continual exchange of photons, the continual forward and reverse chemical reactions - these are not perpetual motion machines, they do not break any laws of thermodynamics or physics in general, and ... I don't know if most high schools teach much about blackbody radiation, but I expect successful high school science students to know about molecular motions and chemical reactions.

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"ANY flux that EXCEEDS the 342 w/m^2 of THE ONLY ENERGY SOURCE is an UNDISPUTABLE VIOLATION OF THE LAW OF CONSERVATION OF ENERGY!"

You can't even add or subtract, Gord. My God, how could you have ever been an engineer?

"Second Law of Thermodynamics: It is not possible for heat to flow from a colder body to a warmer body without any work having been done to accomplish this flow. Energy will not flow spontaneously from a low temperature object to a higher temperature object."

http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw.html#c3

Here are YOUR statements:
"The NET flow of heat can be and often is the difference between two larger values, the heat flow only in one direction and the heat flow in the opposite direction."
"...the "hyperphysics" website seems to imply otherwise, implicitly defining THE flow of heat as the NET of non-work energy flows."
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THE 2ND LAW DOES NOT INCLUDE THE WORD "NET" AT ALL!
YOUR INCLUSION OF THE WORD "NET" IS YOUR "OPINION" AND NOT BASED ON REALITY!
IS THAT CLEAR ENOUGH?
--------------------
Regarding my statement:
"ANY flux that EXCEEDS the 342 w/m^2 of THE ONLY ENERGY SOURCE is an UNDISPUTABLE VIOLATION OF THE LAW OF CONSERVATION OF ENERGY!"

Your reply was:
"You can't even add or subtract, Gord. My God, how could you have ever been an engineer?"

Besides being rude, you have not explained how any Flux could exceed the 342 w/m^2 of THE ONLY ENERGY SOURCE and NOT VIOLATE THE LAW OF CONSERVATION OF ENERGY!!!

Don't you know that ANY energy that exceeds the SOURCE ENERGY means that ENERGY WAS CREATED?

The Law of Conservation of Energy CLEARLY STATES...ENERGY CAN NEVER BE CREATED!

Yet Trenberth's Energy Budget shows that the Earth's surface radiates 390 w/m^2 WHICH IS GREATER THAN 342 w/m^2 (THE ONLY ENERGY SOURCE)!!!

Is 390 GREATER THAN 342?
Where did the "extra" 42 w/m^2 come from?

Come on, Patrick ANSWER these simple QUESTIONS!

Or, are you going to attempt a hilarious re-write of The Law of Conservation of Energy too?
--------------------

I included a defintion of a perpetual motion machine, but you only replied to "part" of the definition.
I will repost what I actually posted:

Perpetual motion
"The term perpetual motion, taken literally, refers to movement that goes on forever. However, the term more generally refers to any closed system that produces more energy than it consumes. Such a device or system would be in violation of the law of conservation of energy, which states that energy can never be created or destroyed."

"Perpetual motion violates either the first law of thermodynamics, the second law of thermodynamics, or both"

"A perpetual motion machine of the first kind produces energy from nothing, giving the user unlimited 'free' energy. It thus violates the law of conservation of energy."

http://en.wikipedia.org/wiki/Perpetual_motion
---
Your response was a number of rambling questions which I will not repeat followed by another unsupported "Opinion":
"THESE phenomena are not what is meant when one speaks of a perpetual motion machine."

Looks like you are ready to re-define what Perpetual Motion is as well!
--------------------
Like I said, your Posts are rife with errors and unsupported rambling opinions.

Replying to all your errors and unsupported rambling opinions is just too tedious.

Your inability to understand even the most basic physics is very apparent from your posts.

However, your demonstated lack of scientific knowledge has not impeded your willingness to re-write some fundamental Laws of Science.

I find this both amusing and astonishing.

It's a good thing that you are an amateur, at least the Public will not be in any danger.

You said....
"I suspect your work with electromagnetic waves was limited to the macroscopic level (and perhaps had nothing to do with thermal emissions, but rather with emission of waves due to some work input - organized electrical currents and magnetic fields, etc.). For shorter wavelengths, particularly those in which the bulk of radiant energy is emitted thermally at temperatures typical of the Earth and atmosphere, or at any higher temperatures, it is convienient to think of photons. Feel free to take a vector sum of energy
fluxes from all linearly superimposed electromagnetic waves if you want to - there is nothing wrong with that, you will get the net energy flux, but this does not change the fact that photons often go by the same location in space in many directions, including opposite directions,...."

And, You said...
"Your interpretation of it requires miraculous events - that an object emits or does not emit a photon depending on the temperature of another object at some distance and at a future time."

"It is not as fundamental as gravity and electromagnetism,...."

"It is not a result of some 'physical force' that actually drives heat from a hot object to a cold object in the same way that gravity pulls matter together and electromagnetism describes the interaction of charged particles, etc."
----------
Your statements show that you do not understand Radiative Heat transfer, or even more generally, Electromagnetic Field transfer of energy.

Photons DO NOT PROPAGATE BY THEMSELVES...THEY REQUIRE AN ELECTROMAGNETIC FIELD FOR PROPAGATION.

Heat Radiation
Radiation is heat transfer by the emission of electromagnetic waves which CARRY energy away from the emitting object.
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/stefan.html#c2
---
Properties of electromagnetic waves
"An electromagnetic wave, although it CARRIES no mass, does CARRY energy."
"A more common way to handle the energy is to look at how much energy is CARRIED by the wave from one place to another."
http://physics.bu.edu/~duffy/PY106/EMWaves.html
---
Photon energy is "Carried" by propagating Electromagnetic Fields.

EM Fields are Vector Fields and follow Vector Addition Mathematics.
Photon energy can ONLY be carried in the direction of propagation of the EM field.

If the EM field has a magnitude of zero...it CANNOT CARRY any Photon energy.

If two opposing EM Fields are summed....the Resultant Vector Field can only have ONE magnitude and only ONE direction of propagation.

When summing opposing fields produced by Hot and Cold objects, the Resultant Vector Field will ALWAYS propagate from the Hot object to the Cold object.

There is ZERO EM Field propagation from Cold to Hot and therefore ZERO PHOTON ENERGY can flow from Cold to Hot.

This is NOT a "miraculous event" as you seem to believe!

This is also why the 2nd Law does not use the word "net" in it's description and uses "not possible".

This completely complies with the 2nd Law of Thermodynamics, Heat Transfer equations and validates the Law of Conservation of Energy.
---------------
Further, there is no difference between Electromagnetic Fields produced by macroscopic radiators or microscopic radiators.
They both are described by the same Electromagnetic Field physics.

Note that the Electromagnetic Force is also one of the four fundamental forces ....as is Gravity.

Electromagnetic force
"The electromagnetic force is one of the four fundamental forces. The other fundamental forces are: the strong nuclear force (which holds quarks together, along with its residual strong force effect that holds atomic nuclei together to form the nucleus), the weak nuclear force (which causes certain forms of radioactive decay), and the gravitational force. All other forces are ultimately derived from these fundamental forces."

"In physics, the electromagnetic force is the force that the electromagnetic field exerts on electrically charged particles. It is the electromagnetic force that holds electrons and protons together in atoms, and which hold atoms together to make molecules. The electromagnetic force operates via the exchange of messenger particles called photons and virtual photons."

"The electromagnetic force is the one responsible for practically all the phenomena one encounters in daily life, with the exception of gravity."

http://en.wikipedia.org/wiki/Electromagnetic_force
---
Photon
"In physics, a photon is an elementary particle, the quantum of the electromagnetic field and the basic "unit" of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force. The effects of this force are easily observable at both the microscopic and macroscopic level, because the photon has no rest mass; this allows for interactions at long distances"

http://en.wikipedia.org/wiki/Photon
----------------
This post demonstrates how little you actually understand about Electromagnetic Fields and how they relate to Radiative Heat transfer and the 2nd Law of Thermodynamics.

Your posts are rife with errors and it is a tedious task to point them all out....and, this post was just a minor start.

Of course, you will probably produce a great deal of unsupported rambling opinions and then try to re-write the definitions posted above.

"If two opposing EM Fields are summed....the Resultant Vector Field can only have ONE magnitude and only ONE direction of propagation."..."When summing opposing fields produced by Hot and Cold objects, the Resultant Vector Field will ALWAYS propagate from the Hot object to the Cold object."

Thank you, Gord, for finally admitting that there are opposing fields from the Hot and Cold objects. I don't know why you made such a fuss about Kiehl and Trenberth giving the opposing fields - you could have just done the math to find the resultants.

You missed this part:
There is ZERO EM Field propagation from Cold to Hot and therefore ZERO PHOTON ENERGY can flow from Cold to Hot.

This is NOT a "miraculous event" as you seem to believe!

This is also why the 2nd Law does not use the word "net" in it's description and uses "not possible".

This completely complies with the 2nd Law of Thermodynamics, Heat Transfer equations and validates the Law of Conservation of Energy.
-------------------
This confirms what I have been saying all along:

-The 2nd Law of Thermodynamics is correct as written (surprise, surprise).
-The Heat Transfer equations are correct as written (surprise, surprise).
-The Law of Conservation of Energy is violated if there is any flow of energy from cold to hot (surprise, surprise).
-Back Radiation from a colder atmosphere cannot reach the warmer Earth's surface and cause warming (surprise, surprise).
-Trenberth's Energy Budget violates both the 2nd Law of Thermodynamics, the Law of Conservation of Energy and actual measurements.

"Note that the Electromagnetic Force is also one of the four fundamental forces ....as is Gravity."

Did I ever say otherwise? My point was that the second law of thermodynamics does not operate on the same level - there is no 'second law of thermodynamics' field or force, etc. It is a consequence of the statistics of disorganized processes (whatever forces are involved in those processes).

""The electromagnetic force is one of the four fundamental forces. The other fundamental forces are: the strong nuclear force (which holds quarks together, along with its residual strong force effect that holds atomic nuclei together to form the nucleus), the weak nuclear force (which causes certain forms of radioactive decay), and the gravitational force. All other forces are ultimately derived from these fundamental forces."" (http://en.wikipedia.org/wiki/Electromagnetic_force)

I've known that since before I was 10.

""In physics, the electromagnetic force is the force that the electromagnetic field exerts on electrically charged particles. It is the electromagnetic force that holds electrons and protons together in atoms, and which hold atoms together to make molecules. The electromagnetic force operates via the exchange of messenger particles called photons and virtual photons.""...""The electromagnetic force is the one responsible for practically all the phenomena one encounters in daily life, with the exception of gravity."
" (http://en.wikipedia.org/wiki/Electromagnetic_force)

I've also known that for a long time. I know that the energy flux of an electromagnetic wave is described by the Poynting vector, which is the cross product of the electric and magnetic field vectors - perhaps multiplied by a constant; I don't have all the details memorized but I do understand the concept.

""In physics, a photon is an elementary particle, the quantum of the electromagnetic field and the basic "unit" of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force. The effects of this force are easily observable at both the microscopic and macroscopic level, because the photon has no rest mass; this allows for interactions at long distances"" (http://en.wikipedia.org/wiki/Photon
)

Yep, I've known that for a long time, too.

"Photons DO NOT PROPAGATE BY THEMSELVES...THEY REQUIRE AN ELECTROMAGNETIC FIELD FOR PROPAGATION."
"Photon energy is "Carried" by propagating Electromagnetic Fields."

This may be splitting hairs, but I think the label 'photon' applies to a wave packet in electric and magnetic fields, so it is a but redundant to say that a photon needs electromagnetic fields to propagate. But I agree that photons do propagate by waves in electromagnetic fields.

"EM Fields are Vector Fields and follow Vector Addition Mathematics."
"Photon energy can ONLY be carried in the direction of propagation of the EM field."
"If the EM field has a magnitude of zero...it CANNOT CARRY any Photon energy."
"If two opposing EM Fields are summed....the Resultant Vector Field can only have ONE magnitude and only ONE direction of propagation."
"When summing opposing fields produced by Hot and Cold objects, the Resultant Vector Field will ALWAYS propagate from the Hot object to the Cold object."

What happens when two wave packets (photons) go by each other in opposite directions. Their fields linearly superimpose. So do their associated Poynting vectors. There may be a moment in space and time where the energy flux is zero. BUT, the wave packets, in their linear superposition, continue to propagate and move on. Each photon continues along with its energy.

"There is ZERO EM Field propagation from Cold to Hot and therefore ZERO PHOTON ENERGY can flow from Cold to Hot."

This may be splitting hairs, but if you insist on only ever using the resultant field and not any contributing components, then you cannot say that the field propagation from cold to hot is zero if the field propagation from hot to cold is nonzero. If you are refering to the same field each time, then if the energy flux positive in one direction, the energy flux must be negative in the opposite direction. Hence, the resultant field propagation from cold to hot is negative. (***... in a vacuum and in most ordinary materials. It is possible to have a material with a negative index of refraction, and in such a case, group velocity (which is in the same direction as the energy flux) can be opposite the phase propagation. See also 'metamaterials'.)

"Further, there is no difference between Electromagnetic Fields produced by macroscopic radiators or microscopic radiators.
They both are described by the same Electromagnetic Field physics."

Yes, of course. But your apparent assumption that the only meaningful energy flux is that of the total electromagnetic field doesn't make as much sense when dealing with wave packets emitted and absorbed over time intervals smaller than the time of propagation, and it doesn't make as much sense when dealing with macroscopic effects of microscopic processes.

If you have two antenna and they are continuously emitting and absorbing electromagnetic radiation with no variance in time (outside of the wave cycles themselves), then I suppose taking the energy flux of each set of waves emitted by each antenna individually may seem less meaningful than taking the total energy flux of the electromagnetic field, which - except for the wave cycles themselves - will always be of one value and will always be in one direction (at any one point in space, or zero.

BUT the energy transitions that emit and absorb photons are generally quantized, and a macroscopic object can have many available energy transitions (pairs of occupied and unoccupied energy levels) within any given interval of the spectrum; the density of associated states and the strength of their interaction with photons (in emission and absorption - there is a physical symmetry in that, by the way) help determine optical properties. There can also be many energy transitions (pairs of occupied and unoccupied states) that cannot emit or absorb photons, but in some such pairs, one of the states may also in a pair of states that forms an energy transition that could emit or absorb a photon. Whether an energy transition is available for emiting or absorbing a photon depends on which of the pair of states is occupied. As with the distribution of internal energy among molecules and among their available degrees of freedom (for the energies available - some degrees of freedom are quantized and require a minimum energy available to contribute to heat capacity), there is a tendency for energy to be distributed among states (including photons) in a particular way (for photons, blackbody radiation) when in local thermodynamic equilibrium (a statistical equilibrium, in which individual energy transitions are still occuring, but the reverse transitions occur at the same rate - this equilibrium requires that a sufficient fraction of each set of energy states is occupied so that the rate at which transitions from those states to other states is high enough to balance the rate of the reverse transitions).

The point here is, the "two opposing EM Fields" each consist of many individual photons that are emitted from one object and absorbed in the other (and not all in the same set of opposing directions; they are generally emitted and can be absorbed over a wide range of directions, with exchange among objects generally only limited by the solid angle each encompasses relative to points on the other's surface). Summing the two EM fields in a macroscopic average describes the resultant energy flux on a macroscopic scale, but this does not mean that individual photon emissions and absorptions do not both occur in both objects. And on the microscopic scale, these photons' linear superposition can fluctuate, just as the density of a gas fluctuates on a molecular scale (molecules are concentrations of mass).

"This is NOT a "miraculous event" as you seem to believe!"

Each individual photon is emitted, and then over some nonzero time, propagates to where it is absorbed. If you insist this path never goes from macroscopic colder to macroscopic warmer, then I would like to know either: How is the emission or nonemission of a photon determined by nonlocal conditions at a future time? or: How is the absorption or nonabsorption of a photon determined by nonlocal conditions in the past (because a single photon does not carry information within itself about the temperature of the object which emitted it, only the specific energy transition that emitted it; and remember, in a macroscopic object in local thermodynamic equilibrium, some molecules are more energetic than others, etc.)?

Interference
"In physics, interference is the addition (superposition) of two or more waves that result in a NEW WAVE pattern."
"The principle of superposition of waves states that the resultant displacement at a point is equal to the vector sum of the displacements of different waves at that point. If a crest of a wave meets a crest of another wave at the same point then the crests interfere constructively and the resultant wave amplitude is greater. If a crest of a wave meets
a trough of another wave then they interfere destructively, and the overall amplitude is decreased."

http://en.wikipedia.org/wiki/Interference
-------------------
Electromagnetic radiation
"Interference is the superposition of two or more waves resulting in a NEW WAVE pattern. If the fields have components in the same direction, they constructively interfere, while opposite directions cause destructive interference."

http://en.wikipedia.org/wiki/Electromagnetic_wave
-------------------------------
The Resultant Electromagnetic Vector Field is the ONLY EM field that can be measured at any single point.

It is, in fact, a NEW WAVE produced by interference and the component parts cannot be measured at a single point.

The Resultant EM Field will be continuous if the components are continuous.

For Heat Transfer by Radiation between bodies, as long as each body has a temperature, the resultant EM field will be continuous.

If one body maintains a temperature that is warmer than the cooler body the continuous resultant EM Field will only propagate from warm to cold.

There will be zero EM wave propagation from cold to warm and therefore there will be zero energy transfer from the cold body to the warm body.

"chris at 19:00 PM on 29 April, 2009
Re #327
Your timings and causes are incorrect Quietman. The collision of the African and Eurasian plates that "squeezed out" the Tethys Ocean and drove the crumpling and nappe formation that raised the Alps occurred 20-ish million years ago. It had nothing to do with the PETM."

I guess that you should take that up with Dr. Chris Beard (Ph.D.) since I took that right out of his book "The Hunt for the Dawn Monkey". It happens to be key to the study of primate evolution and how we got to Africa from Asia. The mountains did not rise until well after the collision and are not proof that the collision took place as late as only 20 million years ago, especially since our ancestors were in Africa MUCH earlier. Morotopithecus was already bipedal and walking around Africa 23 million years ago.Early Eocene Map (Before landbridge)Miocene Map (after landbridge)
Better stick to subjects that your familiar with. Oh wait, I forgot, you not familiar with those facts either.

The Solar Grand Maximum that went on for about 70 years has ended. The 30 year or so PDO uptrend that combined with the Solar Grand Maximum to produce the late-20th-century temperature run up has started its 30 year downtrend. The PDO downtrend combined with the quiet sun is going to result in continued planet cooling. The sun has not been this quiet this long since 1913. Sunspot changes may be a catalyst for cloud changes and therefore have much greater influence than TSI.

PETM was not intended, Eocene Optimim was intended, the PETM marks a spike that begins the EO when prosimians such as Eosimias were evolving in China shortly after India met Eurasia. In the first map Africa and India are have not closed the gap. VERY active tectonics, unbelieveably active movements of continental masses. Geologically speaking super fast. PE of the Earth.

Sometimes the possibilities for unknown quantities can be bracketed by known quantities.

Most of the geothermal heat escaping the Earth is through slow conduction through rock, not generally subject to rapid fluctuations (mere 1000s of years) on a regional or global scale. (Depending on how deep hydrothermal circulations penetrate, that portion of heat transport may be locally quite variable, but it depends on some more steady supply of heat from below.)

From the thermal conductivity and thermal gradients, a heat flux can be estimated.

The average concentrations of major heat producing radioactive isotopes has been estimated in various rock types. Understanding of geophysics, geochemistry, plus data, yields an understanding of how those isotopes are likely distributed within the Earth; generally, they are concentrated in the crust (especially continental crust) relative to the mantle, and especially relative to the core.

Mantle convection rates can be estimated from continental drift; there is also seismography and physics. Core convection (at least partly driven by latent heat of inner core growth, compositional variations formed by inner core growth, and cooling from above) is linked the the magnetic field. Possible long-term global cooling rates can be bracketed by evidence of past tectonic behavior and knowledge of heat sources (including tidal deformation). Etc, Etc, etc...

PS while one point in space and time has only one measurable value of each of the electric field and the magnetic field, spatial variations can be analyzed mathematically (Fourier analysis) to find linearly superimposed components that have various wave vectors. Systems that resonant at different frequencies will detect different parts of the spectrum. Photons with different energies will be absorbed or emitted by associated energy transitions.

Patrick
As we discussed in the Volcano thread, Continental Drift was considered a steady gradual process until quite recently. Not we know that it is not. The recent increase alone is proof of that (I won't rehash details here). I know that you do not accept the hypothesis of a tectonic driver of climate, this is understandable as it is an opposing hypothesis, but I think with a little more study it will prove to be important to understanding climate.

I accept tectonic drivers of climate on the millions of years time scale via geographical changes (directly forcing climate changes, also shaping some aspects of the carbon cycle) and geologic CO2 emissions. (Obviously this can all affect biological evolution and that will have climatic effects as well.)

(I also accept that climate can affect geology - an example is that dry conditions have something to do with the heights achieved by the Andes, though I forget the details (lack of erosion leading to less sediment fed into the subduction zone?))

I do not see any reason to expect changes in the geothermal heat flux itself to have a significant climateic impact on regional to global scales over most of geologic time.

Patrick
Re: "I do not see any reason to expect changes in the geothermal heat flux itself to have a significant climateic impact on regional to global scales over most of geologic time."
See the maps I posted links to on page 14 here and the additional maps in the "Climate's changed before" thread.
I'll try to explain in that thread.

I was talking about the PETM (Paleo-Eocene Thermal Maximum. You should try to be a bit more specific/explicit in your discourse! The PETM had nothing to do with the collision of the African and Eurasian plates (see post # 329 on this thread) and is characterised by a massive spike in the atmospheric CO2 concentration (possibly originally in the form of methane) and is contemporaneous with the opening up of the North Atlantic at the nascent plate boundary.

The warm Eocene period is itself very likely due to high CO2 concentrations as indicated by proxy CO2 measurements from sediments from those periods [**]. Likewise the long, slow cooling in the middle to late Eocene is associated with a continual slow decrease in atmospheric CO2 concentrations as indicated by proxy CO2 measures from cores [***].

There’s very little evidence that it is heat from (changes in) tectonic activity that generates warming above background levels. The geothermal flux is just too small (around 0.1 W/m2 compared to the greenhouse-augmented solar flux absorbed by the Earth’s surface of over 150 W/m2). Nevertheless recent evidence supports a fundamental role for plate tectonics and continental drift in Eocene warming/cooling. In this case it is the Northward movement of the Indian plate towards Asia that is proposed as the source of the slow, slow ramp up of atmospheric CO2 (and associated warming) and the slow,slow loss of CO2 that progressed into the Oligocene and gave the world Antarctic glaciation. The scenario is as follows [****]:

a. As the Indian plate drifted Northwards through the late Mesozoic and into the early Cenozoic (Paleozoic-early Eocene [*]), the carbonate-rich deposits on the ocean floor of the Asiatic margin of the Tethys ocean were subducted beneath the Asiatic plate resulting in their decarbonation and the steady release of CO2 over millions of years. Around 65 MYA and lasting for about 1 million years the massive Deccan traps formation was created in the centre-West of the “Indian” continent as basaltic outpouring from eruption of a mantle plume.

b. This “CO2 factory” ceased around 50 MYA as the ocean between the continents was consumed. Continental collision resulted in strong uplift in the collision zone, producing enhanced rainfall.

c. The movement of the Indian continent and its massive Deccan Trap into the equatorial belt, together with the enhanced rainfall arising from mountain formation produced strong weathering. Basaltic rocks like the Deccan are strong consumers of CO2 (5-10 times more CO2 consumed compared to granitic rocks under similar weathering conditions). From around 50 MYA through to the late Eocene, CO2 levels dropped, the Earth cooled and 35 MYA or so ago the Earth was sufficiently cool for a substantial ice cap to form in Antarctica…..

([*]for a temporal evolution of global temperature during these periods see:

abstract: Quantification of the atmospheric concentration of CO2 ([CO2]atm) during warm periods of Earth's history is important because burning of fossil fuels may produce future [CO2]atm approaching 1000 parts per million by volume (ppm). The early Eocene (~56 to 49 million years ago) had the highest prolonged global temperatures of the past 65 million years. High Eocene [CO2]atm is established from sodium carbonate minerals formed in saline lakes and preserved in the Green River Formation, western United States. Coprecipitation of nahcolite (NaHCO3) and halite (NaCl) from surface waters in contact with the atmosphere indicates [CO2]atm > 1125 ppm (four times preindustrial concentrations), which confirms that high [CO2]atm coincided with Eocene warmth.

abstract: The relation between the partial pressure of atmospheric carbon dioxide (pCO2) and Paleogene climate is poorly resolved. We used stable carbon isotopic values of di-unsaturated alkenones extracted from deep sea cores to reconstruct pCO2 fromthe middle Eocene to the late Oligocene (45 to 25 million years ago). Our results demonstrate that pCO2 ranged between 1000 to 1500 parts per million by volume in the middle to late Eocene, then decreased in several steps during the Oligocene, and reached modern levels by the latest Oligocene. The fall in pCO2 likely allowed for a critical expansion of ice sheets on Antarctica and promoted conditions that forced the onset of terrestrial C4 photosynthesis

abstract: India's northward flight and collision with Asia was a major driver of global tectonics in the Cenozoic and, we argue, of atmospheric CO2 concentration (pCO2) and thus global climate. Subduction of Tethyan oceanic crust with a carpet of carbonate-rich pelagic sediments deposited during transit beneath the high-productivity equatorial belt resulted in a component flux of CO2 delivery to the atmosphere capable to maintain high pCO2 levels and warm climate conditions until the decarbonation factory shut down with the collision of Greater India with Asia at the Early Eocene climatic optimum at ≈50 Ma. At about this time, the India continent and the highly weatherable Deccan Traps drifted into the equatorial humid belt where uptake of CO2 by efficient silicate weathering further perturbed the delicate equilibrium between CO2 input to and removal from the atmosphere toward progressively lower pCO2 levels, thus marking the onset of a cooling trend over the Middle and Late Eocene that some suggest triggered the rapid expansion of Antarctic ice sheets at around the Eocene-Oligocene boundary.

Chris
The PETM is a spike of zero duration in geologic time. It represents an event that caused a heat peak but not a continued warming as it immediately cooled. The cause of this spike is unknown and as it had to lasting effect is irrelevant. The later climb represents changes in ocean currents in direct response to the Med being cut off from the Pacific.

Patrick
by "blowing smoke" I mean bad science procedures. They assume AGW and try to make the past fit the hypothesis rather than study of the period and let the science speak for itself WITHOUT ASSUMPTIONS.

ps
Ice cores have already proven that CO2 follows temps, not the other way around. This means that regardless of how much CO2 there was, it is irrelevant. It was NOT the cause and only confirms that CO2 increases with increased temperatures some time afterward, that's all.

#361. The PETM obviously didn't have "zero duration". The greenhouse-induced warming took up to 20,000 years with a longer recovery time. It produced a large temperature rise, ocean acidification, and is associated with expulsion of a very large amount of 13C-depeleted carbon into the atmosphere (and oceans). It caused very significant extinctions of marine organisms.

#363/364:

The science is speaking for itself Quietman, based on careful assesment of evidence....and science is nothing if not evidence-based.

The fact is that the PETM is associated with very high atmospheric CO2 levels, and these were 13C-depleted (possibly originating in methane clathrates), and the oceans acidified. These are all characteristics of warming from greenhouse forcing and CO2 uptake by the oceans.

Likewise the warming of the Eocene is linked to high atmospheric CO2 levels and cooling towards the late Oligocene was sequentially reduced CO2 levels.

We can be scientific and assess the relationship between raised/reduced temperatures and raised/reduced CO2 durng these periods. We can inspect the ice age transitions and observe that the glacial-interglacial transitions were generally associated with a temperature rise of 5-6 oC and raised CO2 of around 90 ppm (180-270 ppm through several of the transitions in the ice core record). Thus a global temperature rise/fall of around 1 oC recruits/sequesters around 15 ppm of CO2 into/from the atmosphere.

The peak of the Eocene was perhaps 6 oC warmer than now. Atmospheric CO2 levels were as high as 1500 ppm. It's immediately obvious that such high CO2 levels cannot be due to the physicochemical equilibrium between atmospheric and oceanic CO2 that was responsible for temperature-linked CO2 changes during ice age glacial-interglacial transitions. We might account for 100 or even 200 ppm of atmospheric CO2 that way, but we're more than 1000 ppm of atmospheric CO2 out. CO2 levels can't have risen in the manner that you suggest - it's incompatible with the evidence.

And of course the notion that CO2 follows temperature but not the other way round is logically flawed. Any phenomenon/event that releases large amounts of greenhouse gas into the atmosphere must cause the Earth to warm. The Earth warmed rather quickly during the PETM as a result of the massive enhancement of greenhouse gases that has left multiple traces in the sedimentary record. That's what the evidence shows.

Re 359 - when we say that it is only about 0.1 W/m2 (and, actually, I think that's rounded up from maybe 0.08 W/m2), we - here I am assuming what others mean - we don't mean that it is always exactly the same. But it cannot vary much very fast on large (regional and global) scales because much of the heat near the surface had to come from below, etc... a sudden increase in the heat flux would deplete the near-surface heat and it would take time for heat from below to build up the near-surface heat to a point where it can flow out at the same rate... and of course, the rate of radioactive decay within the crust is basically set in stone once the stone forms. Larger changes have to take millions of years... and there are negative feedbacks that would keep it from getting much larger or much smaller than what it would be following a billions-of-years long cooling trend.

Re 363 - why, then, should you assume that changes in geothermal heat fluxes and continental arrangements should have any effect? - even though the later obviously and easily could, it would be an assumption (that certain physical laws held for other time periods, etc.) that it ever did... (Of course it (changes in geography) did, and of course CO2 did, etc.)

Re: "The peak of the Eocene was perhaps 6 oC warmer than now. Atmospheric CO2 levels were as high as 1500 ppm."

In parts of the Mesozoic it was not as hot but had higher levels of CO2, There is zero correlation.

Re: "Likewise the warming of the Eocene is linked to high atmospheric CO2 levels and cooling towards the late Oligocene was sequentially reduced CO2 levels."

No it's increased O2 caused cooling, not reduction of CO2. One is a cause and the other is a consequent.

Re: "We might account for 100 or even 200 ppm of atmospheric CO2 that way, but we're more than 1000 ppm of atmospheric CO2 out. CO2 levels can't have risen in the manner that you suggest - it's incompatible with the evidence."

No, it's not when you take into account the massive increase in tectonic activity and bombardment from space of asteroids and comets (from about 70mya through the Miocene). Think just a minute of how much NOx and Methane was being released from former seabeds not exposed to the air.